Figure 4.

HURP is required for Ran-dependent microtubule nucleation in the absence of MCAK. (A) Western blot of HURP, MCAK, and EB1 (as loading control) comparing dilutions of total untreated Xenopus mitotic egg extracts and mock-depleted, HURP-depleted (ΔHURP), MCAK-depleted (ΔMCAK) and double depleted (ΔMCALΔHURP) extracts. (B) Ran-induced nucleation assay. Mock, ΔMCAK, and ΔMCAKΔHURP extracts were incubated with Cy3-labeled tubulin, 10 μM RanQ69L, and, where indicated, αTPX2 antibodies and xlHURP and fixed at 10 min. Scale bar, 15 μm.